The inventive concepts relate to a solar cell and a method of fabricating the same and, more particularly, to a solar cell including a negative charge layer and a method of fabricating the same.
A solar cell is a photovoltaic energy conversion system that converts solar energy outputted from the sun into electrical energy. Various kinds of solar cells (e.g., silicon solar cells, dye-sensitized solar cells, quantum dot-sensitized solar cells, and solar cells including copper-indium-gallium-selenium (CIGS)-based materials) have been developed to improve photovoltaic conversion efficiency.
For example, Korean Patent Publication No. 10-2013-0102667 (Korean patent application No. 10-2012-0023636) discloses a dye-sensitized solar cell that uses a semiconductor electrode layer including metal oxide nanotubes containing metal nanoparticles. In addition, Korean Patent Registration No. 10-1294935 discloses a quantum dot-sensitized solar cell that includes a metal oxide layer having a plurality of protrusions formed at predetermined intervals to improve photovoltaic conversion efficiency.
Meanwhile, the silicon solar cell uses a P—N junction diode and generates electrical power by exciting electrons using photons having energy equal to or greater than band-gap energy.
The silicon solar cell may have the photovoltaic conversion efficiency of 25% or less, so silicon solar cells capable of improving the photovoltaic conversion efficiency should be developed to use the silicon solar cells in earnest.